JPH0632588A - Operating condition display device for construction machine - Google Patents

Abstract

PURPOSE:To judge relation between the present operating condition and the rated load easily and exactly by setting a rated load curve extending over the whole circumference of a crane and the like, and displaying this curve, the line segment to indicate the supending load and the turning angle of a boom on a display device. CONSTITUTION:In a computation control device 20 of a crane, the working radius R of suspending goods is computed based on the output of a boom length sensor 11 and a boom angle sensor 12 LB, phi, and the load W due to the suspending goods is computed based on the boom length LB, the boom angle phi, and the output P of a cylinder output sensor. Further, the rated load in response to the overhang quantities d1-d4 by an outrigger jack horizontal overhang quantity sensor 14 and the working radius R is computed as to each turning angle theta of an upper turning body, and hence the rated load curve extending over the whole circumference is set. The rated load curve set in this way, the present suspending load W, and the turning angle theta of the upper turning body detected by a turning angle sensor 15, are displayed on the same screen of a display device 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, in a construction machine such as a crane having an upper swing body such as a swingable boom, sets a rated load according to the outrigger extension state of the outrigger jack and effectively displays this. The present invention relates to a work status display device that does.

[0002]

2. Description of the Related Art In general, it is important to prevent buckling or overturning during the turning operation of the construction machine as described above. Therefore, when the working condition exceeds the safety range, it is forcibly forced. Various safety devices have been proposed that automatically stop the operation of a boom or the like. Conventionally, in such a device, the allowable condition is set equal over the entire 360 ° regardless of the turning angle. However, the outrigger jack provided on the crane is not always perfectly horizontally projected and has a small width. Since the horizontal extension amount of some outrigger jacks may differ depending on the work place such as a road, in this case, it is necessary to change the allowable condition depending on the turning angle. For this reason, there is a demand for the development of a work status display device that enables the driver to accurately ascertain under what conditions the construction machine is currently operating.

For example, in Japanese Unexamined Patent Publication No. 3-73795,
A device has been proposed in which a load factor is calculated over the entire circumference based on a boom posture and a boom load, and the load factor image is displayed on a load factor scale.

Further, in Japanese Patent Laid-Open No. 3-177299, the limit work area of the boom is set according to the horizontal extension amount of each outrigger jack, and the work area of the boom is the same as the work radius and turning angle of the boom. What is shown on the screen is shown.

[0005]

[Patent Document 1] Japanese Patent Application Laid-Open No. 3-73795
The device disclosed in Japanese Patent Publication only displays the load factor on the display and does not directly display the actual workable area. Therefore, it is difficult for the user to grasp the safe driving area at a glance. is there. For example, when the boom is erected to reduce the working radius, the load factor image contracts toward the center point, which gives the user a feeling of strangeness. In addition, it is difficult to intuitively grasp how much the current lifting state has for the rated load.

In the device disclosed in Japanese Patent Laid-Open No. 3-115091, since the workable area is displayed only after the load is hung, it is possible to accurately grasp the movable range from the state where the load is actually lifted. However, it is difficult to determine how much load can be hung at the current position or how much load can be added before actually hanging the load, and after lifting the load. However, it is not possible to grasp how much the current lifting load has relative to the rated load. In addition, for construction machines such as cranes, it is strongly requested to take measures such as alarm when the load factor (ratio of actual lifting load to rated load) exceeds a certain value. In a crane equipped with, it is not possible to know to which position the alarm should be issued.

In view of such circumstances, the present invention provides a work status display device for a construction machine such as a crane, which displays information for easily and accurately grasping the relationship between the current work status and the rated load. With the goal.

[0008]

According to the present invention, there is provided a work state display device for a construction machine, comprising a revolving upper swing body and a support member capable of overhanging, and a load is suspended at a predetermined position of the upper swing body. That is, a lifting load detecting means for detecting a lifting load of the revolving superstructure, a working radius detecting means for detecting a working radius of the upper revolving superstructure, and a swing angle detecting means for detecting a revolving angle of the upper revolving superstructure, Support member detecting means for detecting the amount of overhang of each support member, and full circumference rating for setting a rated load curve over the entire circumference by calculating a rated load according to the working radius and the amount of overhang of each support member for each turning angle The load calculation means and the display means for displaying the rated load curve set by the all-round rated load calculation means and the current lifting load and turning angle on the same screen (claim 1).

Here, the distance from the swing center point of the upper swing body to the rated load curve and the distance from the swing center point to the current display point of the lifting load are the ratio of the rated load at each swing angle to the maximum rated load. It is preferable to set based on (Claim 2).

Further, by displaying an equal load factor curve connecting positions corresponding to a constant load factor inside the rated load curve, a more excellent effect as described later can be obtained (claim 3).

[0011]

According to the apparatus of the first aspect, the movable range of the upper revolving structure is clearly indicated by the rated load curve set by the all-round rated load calculation means regardless of the presence or absence of the suspended load. By displaying the hoisting load and the turning angle of the upper swing body on the same screen as the rated load curve, the operator can grasp the relationship between the rated load and the current working state at a glance.

Further, according to the apparatus of claim 2, the distance from the swing center point of the upper swing body to the rated load curve is not set on the basis of the actual rated load itself, but the maximum rated value. Since it is set based on the ratio of the rated load at each turning angle to the load, the size of the rated load curve hardly changes even if the rated load increases or decreases due to changes in the working radius during operation, etc. Can be used effectively. Moreover, the relationship between the rated load curve and the current work state is always displayed stably.

According to the apparatus of claim 3, the equal load factor curve is displayed in addition to the rated load curve, so that the driver can more easily grasp the load factor at each position. It will be possible.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Although a crane is disclosed here as an example of a construction machine, the present invention can be applied to various construction machines including an upper swing body.

The crane 10 shown in FIG. 15 is equipped with a boom foot (constituting an upper swing body) 102 capable of swinging about a vertical swing axis 101.
A telescopic boom B composed of _N boom members B _{1 to} B _N is attached to the. The boom B is configured to be rotatable (ravelable) about a horizontal rotation shaft 103, and a suspended load C is suspended by a rope 104 at the tip (boom point) thereof. In the following description, Bn
(N = 1, 2, ..., N) indicates the n-th boom member counted from the boom foot 102 side.

Outrigger jacks 105 that project laterally are provided at four corners on the front, rear, left and right of the lower frame of the crane 10. Each outrigger jack 105
The horizontal overhang amount can be set individually.

The crane 10 includes a boom length sensor 11, a boom angle sensor 12, a cylinder pressure sensor 13, an outrigger jack horizontal overhang amount sensor 14, a turning angle sensor 15, a turning angular velocity sensor 16, as shown in FIG.
And a rope length sensor 17 are provided, and detection signals of the respective sensors are input to the arithmetic and control unit 20. From the arithmetic and control unit 20, an alarm device 31, a display unit 32 having a display screen, and a turning drive are provided. Hydraulic system 33
A control signal is output to.

FIG. 2 shows a functional configuration of the arithmetic and control unit 20. The arithmetic and control unit 20 is roughly configured to perform two operations: 1) arithmetic control regarding load factor and 2) arithmetic control regarding turn of boom.

1) Functional configuration relating to load factor calculation control In the figure, the work radius calculating means 21 operates the suspended load C from the boom length LB and the boom angle φ detected by the boom length sensor 11 and the boom angle sensor 12, respectively. The radius R is calculated. The lifting load calculation means 22 uses the boom length LB, the boom angle φ, and the cylinder pressure sensor 13.
The load W by the suspended load C actually lifted is calculated from the cylinder pressure p of the boom upper detected by.

The load factor calculating means 23 includes a hoisting load W of the boom B calculated by the hoisting load calculating means 22, a turning angle θ detected by the turning angle sensor 15, and an all-round rated load calculating means 24 described later. Based on the calculated rated load Wo for each turning angle θ, the ratio of the actual lifting load W to the rated load Wo, that is, the load factor W / Wo is calculated.

First warning control means (first actuation means) 29
1 outputs a control signal to the alarm device 31 to issue an alarm when the load ratio W / Wo calculated by the load ratio calculating means 23 becomes 90% or more. The first stop control means (first actuating means) 292 is configured to control the load factor W / W.
When o exceeds 100%, a control signal is output to the hydraulic system 30 to forcibly stop the crane operation except the turning operation.

By the above means, the load factor W / Wo is calculated and the safe operation is controlled based on the load factor W / Wo.

2) Functional configuration relating to calculation control of boom swing The all-round rated load calculation means 24 uses the work radius R and the horizontal extension amount d ₁ of each outrigger jack 105 detected by the outrigger jack horizontal extension amount sensor 14. ~
Based on d ₄ , the entire circumference rated load of the crane 10, that is, the load (rated load) Wo within a safe range at the working radius R at that time is calculated for all turning angles θ. Specifically, as shown in FIG. 3, the forward capacity calculating means 241, the outrigger jack mode determining means 242,
A lateral capacity calculating means 243, a flatness calculating means 244, an inflection angle calculating means 245, an interpolation calculating means 246, and a curve setting means 247 are provided, and the rated load Wo set here is a relational expression with the turning angle θ. It is given by Wo = f (θ).

The remaining angle calculating means 25 calculates a remaining angle θc at which the boom B can turn from the current position to reach the rated load curve.

The braking angular acceleration calculating means 26 includes the working radius R, the boom length LB, the boom angle φ, and the angular velocity sensor 1.
The actual braking angular acceleration β is calculated based on the angular velocity Ωo and the swing diameter 1 (L) of the suspended load which are respectively detected by 6 and the rope length sensor 17. Specifically, FIG.
Boom inertia moment calculating means 26 as shown in FIG.
1, a permissible angular acceleration calculation means 262 and an actual angular acceleration calculation means 263 are provided to prevent the swinging of the suspended load C when the crane is stopped, and to consider the lateral bending strength of the boom B against the inertial force during forced stop. Calculate the angular acceleration β.

The required angle calculating means 27 calculates the angle (required angle) θr at which the boom B turns from the time when the braking is started at the braking angular acceleration β to the time when the boom B is stopped based on the angular velocity Ωo before the start of the turning braking. It is a thing. The allowance angle calculation means 28 calculates the allowance angle Δθ which is the difference between the remaining angle θc and the required angle θr.

The second warning control means 293 outputs a control signal to the alarm device 31 to issue an alarm when the calculated margin angle Δθ becomes a predetermined value or less. The second stop control means (second actuating means) 294 is arranged so that the above margin angle Δ
When θ becomes 0, a control signal for the motor in the hydraulic system 33 is output to brake and stop the swing of the boom B by the braking angular acceleration β, and the operation radius R is further increased from this point. It is forcibly stopped.

By the above means, the rated load curve over the entire circumference is set, and the safe operation is controlled by comparing this with the current working condition.

Next, the contents of calculation and the contents of control that the arithmetic and control unit 20 actually performs will be described.

1) Arithmetic control regarding load factor The work radius calculation means 21 first obtains a work radius R'which does not take into account the flexure of the boom B and an error ΔR due to the flexure of the boom B based on the boom length LB and the boom angle φ. ,
The working radius R is calculated from both. Lifting load calculation means 2
2 calculates the load W of the suspended load C actually lifted from the calculated work radius R, boom length LB, and cylinder pressure p. The full circumference load rating calculation means 24 uses the procedure described later to determine the current working radius R and the outrigger jack 10.
The rated load Wo is calculated over the entire circumference in the form of a function f (θ) of the turning angle based on the horizontal overhang amounts d _{1 to} d _{4 and the} like of FIG. Further, the load factor calculating means 23 calculates the load factor W / Wo based on the rated load Wo and the lifting load W corresponding to the current turning angle θ.

When the load factor W / Wo is 90% or more, an alarm is issued from the alarm device 31 which receives the output signal of the first alarm control means 291. Therefore, the operator loads the load C by the load. It can be known that W is close to the rated load Wo. Further, when the load factor W / Wo exceeds 100%, that is, when the actual load W exceeds the rated load Wo, the crane operation excluding the turning is controlled by the output signal of the first stop control means 292 in order to prevent danger. (Boom B extension
(Looping, hoisting of the suspended load C, etc.) is forcibly stopped.

2) Computation Control for Boom Turning The full circumference rated load calculation means 24 sets a rated load curve according to the working radius R and the horizontal overhang amounts d _{1 to} d ₄ of the outrigger jacks 105.

The setting operation will be described with reference to the flowcharts of FIGS. 3 and 5 and the explanatory diagrams of FIGS. 6 to 11.

After the work radius R is calculated by the work radius calculation means 21 (step S1 in FIG. 5), first, the work radius R in FIG.
The front capacity calculation means 241 shown in FIG.
Based on, the rated load (first rated load) when the boom B is in the front-rear direction, which is a parameter indicating the forward capacity
W ₀₁ is calculated (step S2). It should be noted that the extent to which the area in front of (and behind) the crane and the area to the side of the crane are determined by the calculation of the inflection angle described later.

The first rated load W that determines this forward capacity
₀₁ is set regardless of the horizontal extension amount of each outrigger jack 105. In this embodiment, the forward capacity calculating means 241 stores the rated load W ₀₁ corresponding to the working radius R for four types of boom lengths LB as shown in FIG. 6, and based on this data, Current boom length L
A first rated load W ₀₁ suitable for B and rated load R is calculated. When the actual boom length LB does not correspond to the above four boom lengths and is a value between them, an appropriate value W is obtained by linear interpolation calculation from the values corresponding to the two boom lengths sandwiching the value. ₀₁ is required.

On the other hand, in the outrigger jack mode discriminating means 242, the present outrigger jack mode (outrigger jack overhang state) is discriminated individually on the left and right sides of the crane based on the horizontal overhang amount of each outrigger jack 105 ( Step S3). As shown in FIG. 8, the horizontal overhang amount of each outrigger jack 105 is 4 in-situ (no overhang), intermediate 1 (small intermediate overhang), intermediate 2 (large intermediate overhang), and full overhang. Therefore, the outrigger jack mode corresponds to any one of the ten types of modes shown in Table 1 below.

[0037]

[Table 1]

Next, the lateral capacity calculating means 243 determines the rated load (second rated load) when the boom B is in the left-right direction, which is a parameter of the lateral capacity, by the working radius R and the outrigger jack mode. ) W ₀₂ is calculated (step S4). Specifically, this lateral capacity calculation means 243
The same data as the graph shown in FIG. 6, that is, the data regarding the rated load W ₀₂ corresponding to the working radius R is stored for each of the above 10 types of outrigger jack modes, and based on this, the second rated load is stored. Set W ₀₂ . The second rated load W ₀₂ is naturally smaller than the first rated load W ₀₁ , but the second rated load W _02
02 means not the maximum load that would impair safety if the lifting load W is larger than this, but the minimum load that can guarantee safety for at least this lifting load, and therefore this second rating Even if a lifting load W larger than the load W ₀₂ acts on the boom B, the safety may not be impaired.

Next, based on the above two allowable radius W _02, W _01, the ratios W ₀₂ / W ₀₁ and is oblateness λ is calculated by the flat rate calculation unit 244 (step S5). Then, the inflection angle of the rated load curve is obtained from the flatness λ and the outrigger jack mode (step S).
6).

The inflection angle means a turning angle at which, when a rated load curve is set, the curve changes from a circular arc having a rated load as a radius to a straight line or from a straight line to a circular arc. The inflection angles set here are the four front, rear, left, and right first boundaries that are the boundaries between the front-back direction area and the left-right direction area of the crane.
Inflection angles θ _F1 and θ _{R1 of} (always set) and
Second inflection angles θ _F2 , θ _R2 set between the inflection angles of
(There are cases where it is set and cases where it is not set).

First, as shown in FIG. 8, the first inflection angle θ _{F1 on} the front side and the first inflection angle θ _R1 on the rear side are respectively the horizontal extension amount of the outrigger jack on the front side and the rear side. It is determined by a simple one-to-one correspondence with the horizontal extension amount of the outrigger jack. For example, the front of the crane is set to θ = 0 °, and the outrigger jack 10 on the front side is set.
Assuming that the horizontal overhang amount of 5 is “in-situ” and the horizontal overhang amount of the rear outrigger jack 105 is “intermediate 2”, the first inflection angle θ _{F1 on} the front side is 5 °, and the first inflection angle on the rear side is 5 °. The first inflection angle θ _R1 is set to 180 ° −30 ° = 150 °, respectively.

In the machine in which the horizontal extension amount of the outrigger jacks can be adjusted in an analog manner, as shown in FIG. 9, a straight line drawn from the center O of the crane to the extension points P _F and P _R of each outrigger jack. Based on the angle,
An angle deviated by a certain adjustment angle ψ from this may be used as the first inflection angle.

The first inflection angles θ _F1 and θ _R1 divide the work area into front and rear areas and left and right areas. In the front and rear areas, an arc having the first rated load W ₀₁ is formed. It becomes the rated load curve as it is.

Next, for the left and right regions, it is first determined whether or not the second inflection angles θ _F2 and θ _R2 are set in this region.

The discrimination criteria will be described. When the points corresponding to the first inflection angles θ _F1 and θ _R1 are connected by a straight line on an arc having a radius of the first rated load W ₀₁ , the straight line is shown in FIG. As described above, there are a case where it does not intersect with an arc having the second rated load W ₀₂ as a radius and a case where it intersects, but when they do not intersect, the above straight line is set as it is as a boundary line in the left and right regions. On the other hand, when the straight line intersects an arc having the second rated load W ₀₂ as a radius, the arc shown in FIG.
As shown in, the angles corresponding to the contact points of the tangent line drawn from the points corresponding to the first inflection angles θ _F1 and θ _R1 are set as the second inflection angles θ _F2 and θ _R2 .

Although the concept of setting each inflection angle is as described above, when actually performing the calculation, the inflection angle calculating means 245 determines whether the boundary line as shown in FIG. Flatness λ at the boundary of the boundary line as shown in FIG.
In addition to storing o, the second inflection angle corresponding to each flattening ratio λ and the outrigger jack mode may be stored for the flattening ratio of the boundary flattening ratio λo or more.

After the inflection angle is set in this way,
By the interpolation calculation means 246, the ratio Wo / W between the rated load Wo and the first rated load W ₀₁ in the region where the boundary line is a straight line.
₀₁ , that is, the intermediate flatness is the first rated load W ₀₁ and the second
It is obtained by interpolation calculation based on the rated load W ₀₂ of the above (step S7). As a result, the oblateness Wo / W ₀₁ over the entire circumference as shown in the graph of FIG. 11 is obtained. The curve setting means 24 is based on the flattening ratio of the entire circumference.
7, the rated load for the entire circumference is set (step S8), whereby the setting operation of the rated load curve is completed.

The setting of the full circumference rated load based on the working radius R can be understood by the three-dimensional graph drawn on the cylindrical coordinates of R-θ-Wo as shown in FIG. The three-dimensional surface SF shown in this graph shows the rated load Wo for each working radius R and turning angle θ.
In F, the unstable region on the side of the vehicle body is a recessed surface SS as shown in the front of the figure when the left front and left rear outrigger jacks 105 are in the intermediate 2 state. Therefore, the line of intersection (closed curve) RP between the solid surface SF and the cylinder CY having the radius of the current working radius R is the rated load curve to be obtained.

FIG. 12 shows an example of the rated load curve set as described above. Wo in the polar coordinate system is shown.
-Defined in the θ plane. In the figure, DL is a rated load curve, and an area surrounded by the rated load curve DL, that is, an area indicated by diagonal lines is a safe work area. Load curve D
L is set individually for both the left and right sides, and is set in consideration of the difference in the amount of horizontal overhang of the front and rear outrigger jacks. Moreover, the rated load curve DL has a shape that is continuous over the entire circumference and is formed by an arc and a straight line that is easy for the user to grasp. The point A indicates the actual load and the turning angle at that time, and the line segment OA (line segment 40) makes it possible to understand the actual work state in the work area at a glance.

On the other hand, the braking angular acceleration calculating means 26 calculates the braking angular acceleration β which takes the lateral bending strength of the boom B into consideration and which does not cause the shake of the load, through the following steps.

First, the boom inertia moment calculation means 26
1 calculates the moment of inertia In of each boom member Bn based on the following equation.

In = Ino · cos ² φ + (Wn / g) · Rn ² Here, Ino represents the moment of inertia (constant) around the center of gravity of each boom member Bn, Wn is the weight of each boom member Bn, and g is Gravity acceleration, Rn, indicates the turning radius of the center of gravity of each boom member Bn.

The allowable angular acceleration calculating means 262 calculates the allowable angular acceleration β ₁ as follows.

Generally, the boom B and the boom foot 102 of the crane 10 have sufficient strength, but when the boom length LB becomes long, a large lateral bending force is applied to the boom B due to the inertial force generated during turning braking. Works. Since the strength burden due to the lateral bending force is maximum near the boom foot 102, the strength is evaluated here based on the moment around the turning axis 101.

Specifically, assuming that the angular acceleration during turning braking is β ', the moment N _B acting on the center of turning of the boom B due to the turning of the boom _B is expressed by the following equation "Equation 1".

[0056]

[Equation 1]

Here, W is the lifting load calculating means 22.
It is the lifting load calculated in. Further, when the rated load related to the transverse bending strength of the boom B is Wo '(Woα': α'is a safety factor), the permissible condition for this strength is expressed by the following equation "Equation 2".

[0058]

[Equation 2]

Substituting the above equation 1 into this equation 2, the following equation is obtained.

[0060]

[Equation 3]

Therefore, the maximum angular acceleration β ', which satisfies the equation "Equation 3", may be set to the allowable angular acceleration β ₁ . The rated load Wo ′ may be set to a constant value,
In consideration of the bending of the boom B and the like, it may be set to a smaller value as the boom length LB and the working radius R increase.

The actual angular acceleration calculating means 263 calculates the allowable angular acceleration β ₁ calculated in this way and the angular velocity sensor 1
6, the actual braking angular acceleration β is calculated based on the boom angular velocity (angular velocity before deceleration) Ωo obtained from the detection result of the rope length sensor 17 and the load deflection diameter l.

The calculation procedure will be described. First, consider a model of a single pendulum as shown in FIG. 13 for the suspended load C suspended from the crane 10. The differential equation of this system is given by the following equations "Equation 4" and "Equation 5".

[0064]

[Equation 4]

[0065]

V = Vo + at where η is the swing angle of the suspended load C, V is the turning speed of the boom point that changes with time t, Vo is the turning speed of the boom point before the start of turning stop (= RΩo), a indicates the acceleration. Differentiate both sides of the above equation "Equation 5" with respect to time t and substitute them into the right side of the equation "Equation 4".
= 0, dη / dt = 0), the following equation “Equation 6” is obtained.

[0066]

[Equation 6]

When this equation is expressed on the phase plane regarding η and (dη / dt) / ω, as shown in FIG.
A circle passing through the origin O (0,0) centering on (-a / g, 0) will be drawn. The time required to go around the circle, that is, the period T in which the state of the simple pendulum changes from the origin O and returns to the same state is given by T = 2π / ω, and therefore the time when the turning stop of the crane is started (point O) to time nT
If the angular acceleration β is set so as to completely stop after (n is a natural number), the crane can be stopped without leaving the swing of the suspended load when the turning is stopped. On the other hand, ω is a constant value determined by the gravitational acceleration g and the shake radius l,
The angular acceleration β capable of stopping turning without load shake can be obtained from the following equation.

Β = −Ωo / nT = −ωΩo / 2nπ
(N is a natural number) Moreover, since | β | ≤ β ₁ is a condition for the transverse bending strength of the boom B, by selecting the smallest natural number n within the range satisfying this condition, the load swing in the minimum required time Without, the actual braking angular acceleration β for stopping the crane can be obtained. The required angle calculation means 27 determines the turning angle required from the start of braking to the complete stop when turning is stopped at the braking angular acceleration β based on the current angular velocity (that is, the angular velocity before braking) Ωo. (Required angle)
Calculate θr. Specifically, when t the time required to complete stop from the start of braking, Ωo + βt = 0, since the two formulas θr = βt ^2/2 + Ωot is established, by eliminating t from both equations, The required angle θr can be obtained.

The allowance angle calculating means 28 calculates an angle at which the vehicle can turn at the current angular velocity Ωo before starting braking, that is, an allowance angle Δθ (= θc-θr). For example, in FIG. 12, assuming that the position where braking must be started in order to completely stop at position C is D, the above margin angle Δ
θ is the angle formed by the straight lines OA and OD.

The second stop control means 294 outputs a control signal to the hydraulic system 33 at the time when the calculated margin angle Δθ becomes 0, for example, when the boom B reaches the position D in FIG. Thus, the turning of the boom B is braked and the operation of increasing the working radius from the present moment is forcibly stopped. At this time, in order to prevent the hanging load C from swinging, the hydraulic motor pressure P _B is set so as to stop at the braking angular acceleration β.

An example of how to calculate the hydraulic motor pressure P _B will be shown. Now, assuming that the sum of the inertia moments regarding the members of the upper swing body other than the boom B is Iu, the torque T _B required for the swing braking is given by the following expression "Equation 7".

[0072]

[Equation 7]

Here, for the acceleration β ″ of the suspended load, η = 0 and dη / dt = under the initial condition t = 0 by using the equations (3) and (5).
If solved with 0, details are not described here, but expressed by the following equation.

Β ″ = (1−cos ωt) · β On the other hand, this torque T _B has a relationship of the following equation "Equation 8", although the conditions on the hydraulic motor side are not described here in detail.

[0075]

[Equation 8]

Therefore, this equation "Equation 8" is replaced with the above equation "Equation 7".
The actual hydraulic motor pressure P _B can be obtained by substituting into

On the other hand, the second warning control means 293 is
When the allowance angle Δθ is not 0 but is equal to or less than a predetermined value, a control signal is output to the alarm device 31 to issue an alarm. This allows the operator to know that the braking will be applied automatically with only a few remaining turns.

Further, the arithmetic and control unit 20 outputs an information signal concerning each value to the display unit 32, and the rated load curve DL, the present load W and the turning angle θ as shown in FIG.
In addition to the line segment 40 indicating both of the above, the lower frame position of the crane 10, the extended position of each outrigger jack 105, the equal load factor curve AL connecting the positions with a constant load factor (90% in the figure), and the like are displayed. Thereby, the operator can grasp at a glance how much the present working condition has for the rated load Wo.

Here, the distance from the turning center O of the crane to the rated load curve DL is not set based on the actual rated load Wo itself, but is set to the maximum rated load (that is, the first rated load). Each turning angle θ with respect to W ₀₁ )
If the all-round rated load calculation means 24 is configured to be set on the basis of the ratio Wo / W ₀₁ (that is, the flatness ratio λ) of the rated load Wo at, the more stable and easy-to-see image can be provided to the driver. . That is, when the distance from the turning center point O of the crane to the rated load curve DL is set based on the value of the rated load Wo itself, the working radius R changes during operation, and the rated load Wo increases or decreases. Then, the size of the rated load curve DL changes frequently, which makes the image very difficult for the driver to see. However, the above distance is the rated load at each turning angle θ with respect to the maximum rated load (that is, the first rated load Wo). By setting it based on the Wo ratio (that is, making the distance dimensionless), the rated load W
The size of the rated load curve DL hardly changes even if o changes a little (especially in the front area, Wo / W ₀₁ =
It becomes 1. ), It is therefore possible to provide the driver with an image that is easy to see at all times. In addition, the size of the display screen can be effectively used. In this case, the length of the line segment 40 is not set based on the value of the rated load Wo itself.
By setting based on the load ratio Wo / W ₀₁ , the relationship between the rated load Wo and the actual lifting load W can be displayed accurately.

Furthermore, in this device, in addition to the above-mentioned rated load curve DL, the equal load factor curve AL is displayed inside it, so that the load factor at each position can be more easily grasped.

Further, in the apparatus of this embodiment, since the rated load curve DL is set to a regular closed curve which is continuous over the entire circumference, an irregular rated load curve which is unpredictable for the operator as in the conventional case. The operator can easily understand the drivable area without feeling a sense of discomfort, as compared with the case in which is set. In addition, since the rated load is set in consideration of the horizontally projected amount of the front and rear outrigger jacks 105, the safety of the machine is surely ensured.

Further, in this apparatus, the required angle | θr for braking and stopping the turning without leaving the swing of the suspended load C
| And the remaining angle θc at which the vehicle can turn before reaching the rated load curve are calculated, and turning braking is started by comparing the two angles. Can stop the body.
Specifically, by issuing an alarm before the two angles match, the operator is prompted to suppress the turning speed, and from the point where the two angles match, the load is not shaken automatically at the braking angular acceleration. Turn braking can be performed. Here, instead of starting the braking from the time when the margin angle Δθ becomes 0, the braking may be performed when the angle Δθ becomes equal to or less than a predetermined value with a margin, or the margin angle Δθ.
It is also possible to set the timing of turning braking and warning based on a margin time Δt obtained by dividing the above by the angular velocity Ωo.

The present invention is not limited to the above-mentioned embodiment, but the following modes can be adopted as an example.

(1) In the apparatus of the above embodiment, it is more effective to display the point (point D in FIG. 12) at which turning braking should be started in addition to the rated load curve DL and the line segment 40. Is.

(2) In the present invention, regardless of the specific shape of the rated load curve, the rated load curve may be freely set according to the working radius of the upper swing body and the protruding state of the outrigger jack. However, as in the above-described embodiment, a continuous rated load curve is set over the entire circumference based on the first rated load W _01, which is a parameter of forward capacity, and the second rated load W ₀₂ , which is a barometer of lateral capacity. By doing so, it becomes possible for the operator to easily grasp the drivable area, and it is possible to realize control in which the outrigger jack is overhanging properly.

(3) In the above embodiment, the "triggerable support member" according to the present invention is provided with the outrigger jacks which are projected to the left and right. The present invention can also be applied to a device that is obliquely extended from the direction and a crawler crane that includes a crawler that can be extended in the width direction of the vehicle body. That is, even in such a crawler crane, when the left and right crawlers are used with different overhanging widths, the hoisting ability changes depending on the turning direction, and therefore the same excellent effect as described above can be obtained by applying the present invention. be able to.

(4) In the present invention, the control of the safe operation based on the load factor is not particularly required, but when such control is performed, it is necessary to calculate the rated load Wo again when calculating the load factor W / Wo. Therefore, there is an advantage that the rated load calculated by the all-round rated load calculation means 24 can be used as it is. Here, as the safety operation based on the load factor, in addition to the above-mentioned warning and forced stop operation, a display for calling attention, for example, an operation of directly displaying the load factor is also effective.

[0088]

As described above, according to the present invention, the rated load curve and the swinging state of the upper swinging body are displayed on the same screen, so that the crane operator can accurately see both at a glance. It is possible to grasp the information, and on the basis of this, it is possible to perform an accurate turning operation in consideration of safety.
In particular, it becomes possible to intuitively predict how much weight the load can be hung before hanging the load and to grasp the margin of the actual lifting load with respect to the rated load during operation.

Further, according to the apparatus of claim 2, the distance from the swing center point of the upper swing body to the rated load curve is set based on the ratio of the rated load at each turning angle to the maximum rated load. Therefore, there is an effect that it is possible to provide a stable image in which the size of the rated load curve hardly changes even if the rated load changes during operation.

According to the apparatus of the third aspect, the equal load factor curve is displayed in addition to the rated load curve, so that the driver can more easily understand the load factor at each value. effective.

[Brief description of drawings]

FIG. 1 is a hardware configuration diagram showing an input / output relationship of an arithmetic and control unit provided in a crane according to an embodiment of the present invention.

FIG. 2 is a functional configuration diagram of the arithmetic and control unit.

FIG. 3 is a functional configuration diagram of an entire circumference rated load calculation means in the arithmetic and control unit.

FIG. 4 is a functional configuration diagram of a braking angular acceleration calculating means in the arithmetic and control unit.

FIG. 5 is a flowchart showing a calculation operation of the above-mentioned all-round rated load calculation means.

FIG. 6 is a graph showing a relationship between a working radius and a hoisting load stored in the all-round rated load calculating means.

FIG. 7 is a graph for explaining a rated load interpolation calculation operation performed by the all-round rated load calculation means.

FIG. 8 is an R-θ plan view showing the relationship between the amount of horizontal overhang of each outrigger jack and the first inflection angle.

FIG. 9 is a view showing another example of the method of setting the first inflection angle Wo−
FIG.

FIG. 10A is a Wo-θ plan view showing a rated load curve when the second inflection angle is not set, and FIG. 10B is a rated load curve when the second inflection angle is set. It is a Wo-theta plan view shown.

FIG. 11 is a graph showing an example of flatness ratios set over the entire circumference.

FIG. 12 shows an example of a set rated load curve Wo−
FIG.

FIG. 13 is an explanatory diagram showing a state of a suspended load as a single pendulum.

FIG. 14 is a graph showing an equation relating to a swing angle and a swing velocity of the suspended load in a phase space.

FIG. 15 is a side view of the crane.

[Explanation of symbols]

10 Crane 105 Outrigger Jack (Supporting Member) 11 Boom Length Sensor (Working Radius Detecting Means) 12 Boom Angle Sensor (Working Radius Detecting Means) 13 Cylinder Pressure Sensor (Hoisting Load Detecting Means) 14 Outrigger Jack Horizontal Overhang Quantity sensor (outrigger jack detecting means) 15 Swing angle sensor (swing angle detecting means) 20 Calculation control device 21 Working radius calculating means (constituting working radius detecting means) 22 Lifting load calculating means (constituting lifting load detecting means) 24 All Circumferential load calculation means 32 Display device (display means) B Boom C Suspended load DL Rated load curve R Working radius W Suspended load Wo Rated load

Claims (3)

[Claims] 1. A work state display device for a construction machine, comprising: a swingable upper swing body and a support member capable of overhanging, wherein a load is suspended at a predetermined position of the upper swing body.
Lifting load detecting means for detecting a lifting load of the revolving structure, working radius detecting means for detecting a working radius of the upper revolving structure, revolving angle detecting means for detecting a revolving angle of the upper revolving structure, and each supporting member. Support member detection means for detecting the amount of overhang, and full circumference rated load calculation means for calculating a rated load according to the working radius and the amount of overhang of each support member for each turning angle and setting a rated load curve over the entire circumference. A working state display device for a construction machine, comprising: a display unit for displaying the rated load curve set by the all-round rated load calculation unit and the current lifting load and turning angle on the same screen. 2. The work status display device for a construction machine according to claim 1, wherein a distance from a swing center point of the upper swing body to the rated load curve and a distance from the swing center point to a current lifting load display point are set. A work state display device for a construction machine, characterized in that the all-round rated load calculation means is configured so as to be set based on the ratio of the rated load at each turning angle to the maximum rated load. 3. The work state display device for a construction machine according to claim 1, wherein the display means is arranged to display an equal load factor curve connecting positions corresponding to a constant load factor inside the rated load curve. A work state display device for a construction machine, comprising: